If you'd just tuned in to the world's most-watched sporting event for the first time Thursday, in time for the opening ceremony and the opening game, hosts Brazil versus plucky underdogs Croatia, you might be forgiven for thinking the World Cup is always this bizarre.

But even those of us who've been around this block a few times were left a little slack-jawed by the day's events. Here's a recap:

WTF Moment 1: The Opening Ceremony

Remember the London Olympics opening ceremony in 2012, a strange cacophony of flying nurses, exploding hills and Kenneth Branagh in a stovepipe hat? Well, Brazil didn't have quite that kind of budget — despite this being the most expensive World Cup ever, most of the money was lavished on still-unfinished stadia.

But what this opening ceremony lacked in budget, it made up for in psychedelic strangeness: under UV lights, people dressed as flowers bounced on giant trampolines. Acrobatic kids had footballs for heads. Dancers displayed the kind of limb-flailing enthusiasm normally reserved for Up With People concerts. A 20-foot mermaid statue (actually more of a mer-ball) was wheeled out. A large football-flower hybrid thing in the center of the field spat out Pitbull and Jennifer Lopez and supremely enthusiastic Brazilian singer Claudia Leitte.

WTF Moment 2: That Own Goal

If you'd put a bet on the opening goal of the World Cup being an own goal — furthermore, an own goal by Brazil — you'd have had a lot of bookies willing to relieve you of your money. And those bookies would now be very poor.

One football fan in India found himself retweeted thousands of times, because he guessed correctly — and also guessed the identity of the scorer — ahead of time. No word yet on whether he put money on it.

Marcelo's 11th minute accidental goal was just one of those unavoidable football moments, and most defenders have done it at one time or another — running back to defend the goal line, you find a ball deflecting off your foot and into the net.

However, most defenders tend not to do it in front of hundreds of millions of viewers, and most such accidents tend not to put the heavily-favored host country behind in the opening game that almost everyone in the world expected them to win.

To his credit, Marcello didn't buckle under the agonizing guilt, and stayed strong throughout the rest of a scrappy game. Croatia tried to press their advantage, but Brazilian legend Neymar was just getting warmed up. Booked for an aggressive elbow in the 27th minute, he too shrugged his misfortune off and scored the equalizer two minutes later.

WTF Moment 3: Spray It, Referee, Don't Say It

Image: Kevin Cox

Even seasoned soccer fans did a double-take when, after awarding Brazil a free kick, Japanese referee Yuichi Nishimura pulled out what appeared to be a can of spray paint to designate where the Croatian defenders should be standing, 10 yards away.

Evidently we all missed the news, a few weeks back, that FIFA had introduced "vanishing spray" into its top competitions — because defenders edging closer to the kicker is such a perennial problem. The shaving-cream-style stuff comes from the Argentinian league and is now used in the MLS — but to the rest of the world, it looked like Nishimura had suddenly decided upon a second career as a graffiti artist.

And indeed, perhaps the ref should consider that second career. In the 70th minute of the game, with the hardscrabble Croatians having shut down every Brazilian attack, Nishimura awarded Brazil a penalty for ... well, for what appears on the replay to be a Croatian defender lightly touching Brazilian forward Fred on the shoulder, and Fred falling over with great theatricality.

Brazil was incredibly lucky minutes later at the other end of the pitch, when a linesman's flag was raised for what he thought was a challenge on the Brazilian goalkeeper by a Croatian forward; his teammate knocked it into the net moments later. The foul was nothing of the sort. For any future campaign to use replay technology in soccer, this game will be Exhibit A.

I think the Croatians have a suggestion for where the referee can shove that can of spray paint. #BRAvCRO#WorldCup2014

Luckily for the host country, Emboaba Oscar put the game beyond all contention in the 90th minute with a low ball that the excellently-named Croatian keeper Stipe Pletikosa almost got a hand to. He also almost saved the penalty. But there's no reward for "almost" in World Cup football, and Brazil ended the day at the top of their group with three points dubiously earned.

Fasten your seatbelts, viewers, because we have a whole month of surprises to go.

Apps to Follow the World Cup

ESPN FC Soccer & World Cup

ESPN’s app for the World Cup featues in-depth analysis and commentary from their team of experts. Customize the experience by choosing your favorite teams to follow and set detailed alerts for everything from in-game substitutions to sore updates to team stats. Users in the U.S. can also see exclusive video highlights from the games. The free app is available for iOS and Android.

FIFA '14

Fans of EA’s FIFA series for Xbox and PlayStation will appreciate the company's latest World Cup iOS offering. In FIFA ’14 players can compete in their own World Cup brackets and customize their team’s lineup to compete with their ideal fantasy team. Those who want to make it more competitive can challenge friends and other online player’s in the game’s multiplayer mode. The free app is available for iOS.

FIFA Official

FIFA Official provides comprehensive profiles of each team, player and coach detailing the past national and World Cup history of each organization. The app has a daily live blog that provides a constantly-refreshed stream of updates from the matches and exclusive photos and videos from the tournament. Super fans can also play games, vote on each game’s “Man of the Match” and sign up for a shot at winning kick-off balls used during the actual games. The free app is available for iOS and Android.

Onefootball Brasil

Choose your favorite teams and get up to the minute updates from both on and off the field. Listen to live commentary from matches and chat with your fellow fans when you connect the app to your Facebook account. The app also has in-depth pre and post-game videos of press conference, interviews and analysis. The free app is available for iOS, Android and Windows Phone.

Travel Portuguese Futebol Edition

For those actually traveling to Brazil to watch the games, Travel Portuguese Futebol Edition from Rosetta Stone will give you a crash-course in essential Portuguese to help you get around the country. The app has simple tutorials that teach you essential words and phrases for learning soccer terminology, taking public transit, ordering food and more. The free app is available for Android.

theScore

theScore is a one-stop shop for all the latest breaking news and updates from your favorite teams and players. Users can set breaking news alerts for individual players or entire teams. Follow along during games with the constantly-updated steam of news about each team and real-time game and score updates. For an even more detailed look, use the app’s shot tracking feature to see exactly how each game’s goals were scored. The app is available for iOS and Android.

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